Sometimes it DOES apply to BPs.
From BBC site.

Honour-based violence in the UK
Murders have sometimes taken place after a family reacted violently to their son or daughter adopting the trappings of western culture.

It's thought that up to 12 honour killings happen every year. They usually occur within South Asian and Middle Eastern families.

One of the most well-known cases is that of Banaz Mahmod, from Surrey, whose murder in 2006 was organised by her father and uncle.

She had left an unhappy arranged marriage after which she started a relationship with another man. The 20-year-old was strangled and hidden in a suitcase which was then buried underneath a Birmingham property.

The police were criticised for mis-handling Ms Mahmod's situation when she contacted them on a number of occasions before her death.

Shahien Taj, from the Henna Foundation, said: "Honour is supposed to be a positive word. Clearly, calling a killing an 'honour crime' is a contradiction of terms.

"A lot of talk and dialogue takes place after a crime has happened, but this is too little too late. If you really want to deal with an issue, you have to unpack it in its true context."

Forced marriages and honour violence
Organisations that deal with honour-based violence also help forced marriage victims, as some of those killed in the name of "honour" were trying to escape coercion into matrimony.

Laws to prevent forced marriages and provide a way out for those already in unconsented unions were introduced in England, Wales and Northern Ireland in November 2008.

Anybody convicted of trying to force someone into a marriage could be jailed for up to two years.

Within the first year, 86 Forced Marriage Protection Orders were implemented.

But as one worker who specialises in the issue said, "The sticking point is that potential victims don't want orders served on their parents - or whoever is responsible - they just want a way out of the situation."

Rise in 'honour' crimes
In December 2009, the Metropolitan Police reported that there had been a huge rise in recorded incidents motivated by "honour."

They said 211 incidents had been reported in London - 129 of which were criminal offences - between April and October.

The increase may partly be due to police being instructed in September 2009 to assume honour crimes have been committed in more situations.

Nazir Afzal, from the Crown Prosecution Service, said: "It will be about making sure we look for the signs so that we don't miss cases."

Detective Chief Inspector Gerry Campbell of the Metropolitan Police told The Guardian, "Young woman are predominately the victims of honour-based violence but we are seeing an increase in young men and boys – it's now about 15% of the total numbers."

He also added that 25% of their cases involved people under the age of 18.